Other Troubleshooting Tips

Make sure you don't have any other apps that connect to your Ledger open (e.g. the Ledger Bitcoin Chrome app, Mist, etc.)

Make sure you have browser support turned ON for MyCrypto.com and OFF for the desktop app.

Make sure you have contract data turned ON.

Make sure that you are confirming any transactions via your Ledger.

Try a different USB cable.

PS

On the other hand, if you're trying to get the Chrome App "Ledger Wallet Bitcoin" to work and it's not reading your Ledger, just make sure that on your Ledger Device you disable "Browser Support" in your app.

MyCrypto is an open-source, client-side tool for generating ether wallets, handling ERC-20 tokens, and interacting with the blockchain more easily. Developed by and for the community since 2015, we’re focused on building awesome products that put the power in people’s hands.